[foreign-abi] RFR: 8239780: FunctionDescriptor factories and combinators should check whether return layout is null [v2]

[Athijegannathan Sundararajan]

On Thu, 17 Sep 2020 14:00:26 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

>> Hi,
>> 
>> I'm going through the foreign-abi JBS issues and taking care of some of the open ones.
>> 
>> This PR adds null checking to the MemoryLayouts passed to the FunctionDescriptor factories and adapter methods,
>> together with a simple test.
>> I've also added an adapter for dropping the return layout, since with the null check, it is no longer possible to pass
>> `null` to drop the return layout. I think having the explicit check, and a separate combinator for dropping the return
>> layout instead will be better for avoiding accidental nulls being used.  Thanks,
>> Jorn
>
> Jorn Vernee has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add FunctionDescriptor API tests

Marked as reviewed by sundar (Committer).

-------------

PR: https://git.openjdk.java.net/panama-foreign/pull/330